Pyrrolo[3,4-c]pyrrole-1,4-dione, 3,6-bis(4-chlorophenyl)-2,5-dihydro-

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1986-01-23, 1986-01-24

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP guideline study according to OECD Guideline 202 without analytical monitoring; determination of test after 24 h

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1981

Deviations:

yes

Remarks:

Test duration was 24 h instead of 48 h.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 50 mg test substance and 2 mg Alkylbenzenesulphonate were mixed with water and made up to 500 mI with water in order to prepare the stock solution. Calculated amounts of the stock solution were given into the water and homogeneously distributed to produce the desired test concentrations.
- Controls: Blank and vehicle control containing reconstituted water according to guideline
- Chemical name of vehicle: Alkylbenzenesulphonate
- Concentration of vehicle in test medium: 4 mg/L in the highest concentration of 100 mg/L (nominal)
- Evidence of undissolved material: yes, initially the test substance appeared homogeneously distributed at all test concentrations. A deposit was
observed after 24h of exposure.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Source: CIBA-GEIGY Ltd., Facilities, Basel, Switzerland
- Age at study initiation: 0 - 24 h
- Method of breeding: Parthenogenetic; Feeding: Suspension of green algae supplemented by trout chow and/or powder milk and/or yeast; in such quantities that food was consumed after 24 hours
- Pretreatment: 24 hours before the start of the test reproductive daphnia are separated from the young by sieving through a 800 micrometer sieve. This operation is repeated immediately before the start and the young daphnia (0 - 24 h old) are retained for the test.
- Feeding during test: None

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Hardness:

240 mg CaCO3/L

Test temperature:

20 ± 1 °C

pH:

7.8 - 8.0

Dissolved oxygen:

7.9 - 8.3 mg/L

Nominal and measured concentrations:

Nominal: 10; 18; 32; 58 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 20 mL test tubes, covered with steel caps (10 mL solution), no aeration during the test
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: According to guideline

OTHER TEST CONDITIONS
- Photoperiod: 16 h/d
- Light intensity: 2000 lux

EFFECT PARAMETERS MEASURED: Immobilization

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca. 1.8

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Table 1. Immobilization

Nominal concentrations (mg/L)	Immobilization after 24 h
	1	2	3	4	total	%
Blank	0	0	0	0	0	0
Vehicle	0	0	0	0	0	0
10	0	0	0	0	0	0
18	0	0	0	0	0	0
32	0	0	0	0	0	0
58	0	0	0	0	0	0
100	0	0	0	0	0	0

Validity criteria fulfilled:

yes

Conclusions:

In an acute dahpnia toxicity study, the substance did not cause any immobilisation up to the nominal test concetration of 100 mg/L.

Executive summary:

The purpose of this study was to evaluate the acute toxicity of the test substance on Daphnia magna similar to OECD TG 202.

Daphnia were exposed to aqueous test media containing the test item at nominal concentrations of 10, 18, 32, 58 and 100 mg/L for 24 hours. Concurrent negative and vehicle (alkylbenzenesulphonate) control groups were also tested.

A static test was performed preparing the concentrations from a stock solution. Precipitated test item was observed after 24 hours. Test item concentration were not measured analytically.

The daphnia were observed at 24 hours for immobilisation.

All validity criteria were met. Immobilisation was not observed either in the treated or in the control groups.The 24-h LC₀values was determined to be 100 mg/L; the LC₅₀ and LC₁₀₀values were determined to be > 100 mg/L.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1986-01-23, 1986-01-24

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP guideline study according to OECD Guideline 202 without analytical monitoring; determination of test after 24 h

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The read-across is performed between two forms of the same substance. The identities of the two forms are describe below.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The source form is 3,6-bis(4-chlorophenyl)-2,5-dihydropyrrolo[3,4-c]pyrrol-1,4-dione (EC-no. 401-540-3), referred to here as PR254. PR254 is an organic mono-constituent substance with a typical purity of > 99.5% (w/w). It does not contain any impurity relevant for classification or labelling of the substance. The target form is the nanoform of the source substance, referred to here as PR254 nanoform. As the source form, it has a typical purity of > 99.5% (w/w) and it does not contain any impurity relevant for classification or labelling of the substance. The PR254 nanoform is spheroidal with a pure polyhedral shape and is not surface-treated.

3. ANALOGUE APPROACH JUSTIFICATION
The two analogue forms have the same structure. Under ambient atmosphere, the specific surface energy of particles increases with decreasing particle size. Therefore, particle aggregate to reach an energy minimum. The driving forces are hydrogen bonds and van der Waals forces (π-π interaction). Substantial energy is required to disperse the PR254 nanoform aggregates to particles that fall under the nanoform definition.
PR254 was been tested extensively addressing information requirements of Annexes VII to IX without identifying any biological target. PR254 nanoform could potentially have biological targets due to the different particle size distribution, which would require processes capable of dispersing the aggregates, e.g. in aqueous milieu. However, both forms have been tested according to OECD Test Guideline 318, demonstrating that PR254 nanoform cannot be dispersed under the condition of the study, i.e. immediately after sonification re-forms aggregates. Also, PR254 aggregates to a large extent, but can be more easily dispersed than the nanoform. The experiments demonstrated that exposure in aqueous milieu will be primarily to aggregates, regardless of the PR254 form.
Therefore, it is concluded that both forms will behave identically in studies, in which they are applied under atmospheric conditions and/or in aqueous milieus, so that for the PR254 nano-form no specific biological targets need to be considered.
As both forms form non-dispersible aggregates in aqueous milieu, read-across of aquatic toxicity studies from the source to the target form is scientifically justified.

4. DATA MATRIX
The data matrix is included as Annex 1 in the assessment report ‘PR254 bulk nano analogue approach 210111’ attached here below under ‘Attached justification’.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

1981

Deviations:

yes

Remarks:

Test duration was 24 h instead of 48 h.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 50 mg test substance and 2 mg Alkylbenzenesulphonate were mixed with water and made up to 500 mI with water in order to prepare the stock solution. Calculated amounts of the stock solution were given into the water and homogeneously distributed to produce the desired test concentrations.
- Controls: Blank and vehicle control containing reconstituted water according to guideline
- Chemical name of vehicle: Alkylbenzenesulphonate
- Concentration of vehicle in test medium: 4 mg/L in the highest concentration of 100 mg/L (nominal)
- Evidence of undissolved material: yes, initially the test substance appeared homogeneously distributed at all test concentrations. A deposit was
observed after 24h of exposure.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Source: CIBA-GEIGY Ltd., Facilities, Basel, Switzerland
- Age at study initiation: 0 - 24 h
- Method of breeding: Parthenogenetic; Feeding: Suspension of green algae supplemented by trout chow and/or powder milk and/or yeast; in such quantities that food was consumed after 24 hours
- Pretreatment: 24 hours before the start of the test reproductive daphnia are separated from the young by sieving through a 800 micrometer sieve. This operation is repeated immediately before the start and the young daphnia (0 - 24 h old) are retained for the test.
- Feeding during test: None

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Hardness:

240 mg CaCO3/L

Test temperature:

20 ± 1 °C

pH:

7.8 - 8.0

Dissolved oxygen:

7.9 - 8.3 mg/L

Nominal and measured concentrations:

Nominal: 10; 18; 32; 58 and 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 20 mL test tubes, covered with steel caps (10 mL solution), no aeration during the test
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: According to guideline

OTHER TEST CONDITIONS
- Photoperiod: 16 h/d
- Light intensity: 2000 lux

EFFECT PARAMETERS MEASURED: Immobilization

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca. 1.8

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No toxic effects occur within the range of solubility.

Table 1. Immobilization

Nominal concentrations (mg/L)	Immobilization after 24 h
	1	2	3	4	total	%
Blank	0	0	0	0	0	0
Vehicle	0	0	0	0	0	0
10	0	0	0	0	0	0
18	0	0	0	0	0	0
32	0	0	0	0	0	0
58	0	0	0	0	0	0
100	0	0	0	0	0	0

Validity criteria fulfilled:

yes

Conclusions:

In an acute dahpnia toxicity study, the substance did not cause any immobilisation up to the nominal test concetration of 100 mg/L.

Executive summary:

The purpose of this study was to evaluate the acute toxicity of the test substance on Daphnia magna similar to OECD TG 202.

Daphnia were exposed to aqueous test media containing the test item at nominal concentrations of 10, 18, 32, 58 and 100 mg/L for 24 hours. Concurrent negative and vehicle (alkylbenzenesulphonate) control groups were also tested.

A static test was performed preparing the concentrations from a stock solution. Precipitated test item was observed after 24 hours. Test item concentration were not measured analytically.

The daphnia were observed at 24 hours for immobilisation.

All validity criteria were met. Immobilisation was not observed either in the treated or in the control groups.The 24-h LC₀values was determined to be 100 mg/L; the LC₅₀ and LC₁₀₀values were determined to be > 100 mg/L.

Description of key information

In an acute dahpnia toxicity study, the substance did not cause any immobilisation up to the nominal test concetration of 100 mg/L.

Additional information

As no effect were observed up to 100 mg/L, no key value for risk assessment is reported.